<p>Consumer brand engagement (CBE) has emerged as a critical mechanism through which brands influence consumer perceptions and behavioural outcomes in social media environments. Despite extensive research on engagement outcomes, limited attention has been given to the cognitive and affective processes through engagement translates into purchase intention, particularly in emerging markets. This study examines the influence of consumer brand engagement (CBE) on social media on brand expected value, brand attitude and purchase intention in the Nigerian fashion industry with age examined as a moderating variable. Using survey data collected from fashion consumers, the proposed conceptual model was tested using structural equation modelling. The results show that consumer brand engagement positively influences brand expected value and purchase intention, while brand expected value and brand attitude significantly predict purchase intention. Unexpectedly, engagement was found to negatively influence brand attitude, suggesting that excessive or highly frequent brand interactions in digitally saturated environments may generate persuasion awareness or engagement fatigue. Additionally, age significantly moderates the relationship between brand attitude and purchase intention. The findings provide new insights into the cognitive-affective mechanisms underlying engagement outcomes and highlight boundary conditions of engagement effectiveness in social media contexts.</p>